X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=libs%2Fcanvas%2Frectangle.cc;h=06a41e074c0fe6514c58b40ca12b7cdfc4778bb3;hb=6d4c0baad3a09d43b5eacb37ea2a2e4c31afcec6;hp=a5aa0a2895852dc4b46c4a9988a0e21254627ea2;hpb=045ef69ac37550cf376d40443555a57a931fe7b0;p=ardour.git

diff --git a/libs/canvas/rectangle.cc b/libs/canvas/rectangle.cc
index a5aa0a2895..06a41e074c 100644
--- a/libs/canvas/rectangle.cc
+++ b/libs/canvas/rectangle.cc
@@ -36,7 +36,6 @@ Rectangle::Rectangle (Group* parent)
 	, Fill (parent)
 	, _outline_what ((What) (LEFT | RIGHT | TOP | BOTTOM))
 {
-
 }
 
 Rectangle::Rectangle (Group* parent, Rect const & rect)
@@ -53,24 +52,14 @@ void
 Rectangle::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
 {
 	Rect self = item_to_window (_rect);
-	boost::optional<Rect> d = self.intersection (area);
+	boost::optional<Rect> r = self.intersection (area);
 
-	if (!d) {
+	if (!r) {
+		std::cerr << whatami() << '/' << name << " not covered by render area! ... " << self << " vs. " << area << std::endl;
 		return;
 	}
-	
-	Rect draw = d.get();
-	static const double boundary = 0.5;
-	const double x_limit = _canvas->visible_area().width();
-
-	draw.x0 = max (self.x0, max (0.0, draw.x0 - boundary));
-	draw.x1 = min (self.x1, min (x_limit, draw.x1 + boundary));
-
-	draw.y0 = max (self.y0, max (0.0, draw.y0 - boundary));
-	draw.y1 = min (self.y1, min (x_limit, draw.y1 + boundary));
 
-	Rect fill_rect = draw;
-	Rect stroke_rect = fill_rect.expand (0.5);
+	Rect draw = r.get ();
 
 	if (_fill) {
 		if (_stops.empty()) {
@@ -78,7 +67,7 @@ Rectangle::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) con
 		} else {
 			setup_gradient_context (context, self, Duple (draw.x0, draw.y0));
 		}
-		context->rectangle (fill_rect.x0, fill_rect.y0, fill_rect.width(), fill_rect.height());
+		context->rectangle (draw.x0, draw.y0, draw.width(), draw.height());
 		context->fill ();
 	}
 	
@@ -86,24 +75,41 @@ Rectangle::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) con
 
 		setup_outline_context (context);
 
-		if (_outline_what & LEFT) {
-			context->move_to (stroke_rect.x0, stroke_rect.y0);
-			context->line_to (stroke_rect.x0, stroke_rect.y1);
-		}
-		
-		if (_outline_what & BOTTOM) {
-			context->move_to (stroke_rect.x0, stroke_rect.y1);
-			context->line_to (stroke_rect.x1, stroke_rect.y1);
-		}
-		
-		if (_outline_what & RIGHT) {
-			context->move_to (stroke_rect.x1, stroke_rect.y0);
-			context->line_to (stroke_rect.x1, stroke_rect.y1);
-		}
-		
-		if (_outline_what & TOP) {
-			context->move_to (stroke_rect.x0, stroke_rect.y0);
-			context->line_to (stroke_rect.x1, stroke_rect.y0);
+		if (_outline_what == What (LEFT|RIGHT|BOTTOM|TOP)) {
+			
+			context->rectangle (self.x0 + 0.5, self.y0 + 0.5, self.width(), self.height());
+
+		} else {
+
+			context->set_line_cap (Cairo::LINE_CAP_SQUARE);
+			
+			/* see the cairo FAQ on single pixel lines to see why we do
+			 * this expansion of the perimeter.
+			 */
+
+			if (_outline_what & LEFT) {
+				/* vertical line: move x-coordinate by 0.5 pixels */
+				context->move_to (self.x0 + 0.5, self.y0);
+				context->line_to (self.x0 + 0.5, self.y1);
+			}
+			
+			if (_outline_what & BOTTOM) {
+				/* horizontal line: move y-coordinate by 0.5 pixels */
+				context->move_to (self.x0, self.y1 - 0.5);
+				context->line_to (self.x1, self.y1 - 0.5);
+			}
+			
+			if (_outline_what & RIGHT) {
+				/* vertical line: move x-coordinate by 0.5 pixels */
+				context->move_to (self.x1 - 0.5, self.y0);
+				context->line_to (self.x1 - 0.5, self.y1);
+			}
+			
+			if (_outline_what & TOP) {
+				/* horizontal line: move y-coordinate by 0.5 pixels */
+				context->move_to (self.x0, self.y0 + 0.5);
+				context->line_to (self.x1, self.y0 + 0.5);
+			}
 		}
 		
 		context->stroke ();
@@ -113,9 +119,19 @@ Rectangle::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) con
 void
 Rectangle::compute_bounding_box () const
 {
-	Rect r = _rect.fix ();
-	_bounding_box = boost::optional<Rect> (r.expand (_outline_width / 2));
-	
+	if (!_rect.empty()) {
+		Rect r = _rect.fix ();
+
+		/* our outlines are always inside our coordinates, but we have
+		 * to ensure that our bounding box fully *contains* the
+		 * rectangle
+		 *
+		 * XXX: or something like that, waffle.
+		 *
+		 */
+		_bounding_box = r.expand (1.0);
+	}
+
 	_bounding_box_dirty = false;
 }